1. Field of the Invention
The invention relates to the field of metallurgy and particularly relates to the field of an abrasion resistant steel utilized in the field of construction, civil engineering and mining.
2. Description of the Related Art
Abrasion resistant steels are utilized in the field of construction, civil engineering and mining such as in power shovels bulldozers, hoppers and buckets to maintain the lives of these machines or their parts. It is well known that the steel having a high hardness possesses high abrasion resistance property. For this purpose a high alloyed steel treated by quenching has commonly been utilized.
Japanese Patent laid open Publication Nos. 142726/19 87, 169359/1988 and 142023/1989 disclose information about the production of the conventional abrasion resistant steel. In these publications the Brinell Hardness of the steel is more than 300. The improvements of these publications, which are aimed at the weldability, the toughness and the workability in bending, and the abrasion resistance property, is realized by increasing the hardness of the steel.
However the property required for abrasion resistant steel has recently become severer and the essential solution to higher abrasion resistance of steel will not be obtained by simply enhancing the hardness of steel. When the hardness of steel is significantly enhanced, the weldability and the workability of steel are deteriorated due to the high alloying and the cost of producing such steels increases significantly. Accordingly in a practical point of view a significant increase in the hardness of abrasion resistant steel faces a difficulty with respect to the workability of the steel.